Bikram Yoga Costa Mesa has a scary proposition for its students Thursday.

Try to take all seven classes in one day.

That’s seven 90-minute fitness classes — 10.5 hours! In a room heated to about 105 degrees. Oh, and if you’re feeling really adventurous, try wearing a Halloween costume while you do it.

The studio first challenged its students to take all seven classes on St. Patrick’s Day — and even handed out Guinness Stout when the final class was over. Four or five students made it through all seven classes that day, but tens of others took multiple classes.

“I did four, and by the fourth class I was high,” studio owner Patrice Simon said last week. “You feel euphoric. Your awareness is heightened. … It’s a test of human strength, will and spirit.”

So far, more than 40 already have signed up to participate in the Halloween challenge. Students will pay for the first class ($18) and can take the rest of the day for free. The studio will provide fruit, veggies and drinks for students between each class.

Anyone can participate, although if you’ve never practiced before, they probably won’t let you try all seven classes. Bikram is different from other forms of yoga in that every class consists of the same series of 26 poses. You can learn more about it here.

“Some people will come and do two,” Simon said. “We’d never push anybody. It’s do what you can.”

I’ve been practicing Bikram sporadically for the past two years, and still, I sit lightheaded outside the room after every class, letting the cool air wash over my tired muscles. I’ll be lucky if I complete two classes, but I’m going to try. First class is at 6 a.m.

Click here for the rest of the scheudule. And check back here for some photos and results.

If you are participating, or think all these people are crazy for pushing the limits, please share your thoughts and experiences below.